Fig. 1

Timeline of the historical milestone for the discovery of protein acylation, and the chemical structures of acyl groups. Since acetylation was identified in 1960s, more than eight kinds of acylation modifications have been discovered, especially after 2009, because of the quick development of mass spectrometry and biochemistry technologies, as well as powerful algorithm methods. The eight kinds of protein acylations mentioned here can be divided into three groups according to their chemical structures. Acetyl- and crotonyl- are short-chain hydrophobic acyl groups. Myristoyl- and palmitoyl- are long-chain fatty acid hydrophobic acyl groups. β-hydroxybutyryl- and lactyl- belong to the polar acyl groups. Succinyl- and malonyl- belong to the negatively charged acidic acyl groups. The short-chain acylation mainly occurs at lysine residues. Whereas myristoylation often occurs at N-terminal glycine or lysine residues, and palmitoylation usually occurs at cysteine, serine or N-terminal amino acid residues